Google has quietly enabled a security feature called Site Isolation for 99% of its desktop users on Windows, Mac, Linux, and Chrome OS. This happened in Chrome 67, released at the end of May. From a report: Site Isolation isn't a new feature per-se, being first added in Chrome 63, in December 2017. Back then, it was only available if users changed a Chrome flag and manually enabled it in each of their browsers. The feature is an architectural shift in Chrome's modus operandi because when Site Isolation is enabled, Chrome runs a different browser process for each Internet domain. Initially, Google described Site Isolation as an 'additional security boundary between websites,' and as a way to prevent malicious sites from messing with the code of legitimate sites.